Measured-service telephone



Dec. 2, 1924.

A. M. CRICHTON MEASURED SERVICE TELEPHONE Filed OCT.. 16, 1920 `2 Sheets-Sheet l INVENTOR.

'BY w05. WW

ATTORNEY A. M. CRICHTON MEASURED SERVICE TELEPHONE FiledOCt. 16, 1920 2 Sheets-Sheet 2 INVENTOR.

ATTORNEY Patented Dec.. 2, 1924i.

UNITED STATES PATENT OFFICE.

ARTHUR M. CRICHTON, F UNIONIlJi/"N, PENNSYLVAIIIA, ASSIGNOR TO MEASUREIJ SERVICE METIER COMPANY, A OGILPORATIQN 0F DELAWARE.

ISEEASURED-SERVICE TELEPHONE.

Application le. Uctocer 16, 1920. Serial No 417,398.

To all fro/tom t may concern.'

Be it known that I, ARTHUR M. CRroHToN, a citizen of the United States, and a resident of Uniontown, in the county of Fayette and State of Pennsylvania, have made a new and useful Invention in a Measured- Service Telephone, of which the following is a specification.

My invention rela-tes to telephone exchange systems and the object thereof is to provide a timing device in connection with such a system which depends for its operation upon the closure of a subscribers hook switch and is automatically effective after a predetermined period to interrupt the talking connection. A further object of my invention is to provide a timing device in connection with a telephone system which automatically signals the operator after the expiration of a predetermined interval after the establishment of a telephonie connection. A still further object of my invention is the provision of a timing device in connection with a telephone circuit which is effective after the expiration of predetermined period to interrupt telephonie communication and which may be reset by the operator prior to the arrival of the period of interruption so that the subscriber may talk for a further period or periods.

In the drawings, Figure 1 is a front elevation of the timing device showing the contact control element in the zero position; Figure 2 is a view similar to Figure 1 but showing the contact operator in a different position; Figure 3 is a side elevation of the timing device; Figure l is a bottom plan view; Figure 5 is a detailed view showing the spring for normally biasing the ratchet cam to a zero position; Figure 6 is a detail view of one of the contacts; and Figure 7 is a view showing the circuit connections.

My present invention relates to a timing device whereby, after the establishment of a telephonie communication between subscribers, the timing device begins to act and continues to operate for a desired interval of time, whereupon the central operator is notified of the approach of the expiration of the period and may then notify the calling subscriber that the call period is about to expire and that if he desires to continue conversation to deposit more toll or record another call after which the timing device is reset to a Zero position.

In accordance with my invention, if the operator should fail to notify the subscriber that the conversation period is about to expire, or should the subscriber disregard the warning, the timing device automatically ell'ects an interruption in the talking circuit at the completion of the predetermined period. Although I have shown my invention related to a telephone meter device such as set forth in my co-pending application, Serial No. 373,674A tiled April 13, 1920, it will be obvious that the timing device herein described might be used in connection with any system for limited telephone serv ice, suoli, for instance` as pay stations. or stations having limited numbers of calls.

Having briefly set forth the objects of my invention and the situations in which it may be used, I will now refer more particularly to the details of construction involved. Briefly, my construction comprises a motoroperated interrupting device for interrupting telephonie communication after a predetermined time and is provided with controlling circuits, one a holding circuit and the other an actuating circuit more particu` larly hereinafter referred to. The motor device, as shown in Figure 1, is enclosed within a suitable casing 9 and it is arranged to be situated in any convenient or desirable place in a telephone exchange. The device includes a face plate 10, preferably made of non-magnetic material and supporting at the sides thereof a signaling contact 11 and an interrupting contact 12. The Contact 11 comprises two leaf spring contact elements 13 and 14 separated from each other and from the face plate by any suitable insulating material, and the contact 12 comprises two leaf spring contact elements 15 and 16 separated from each other and from the face plate by insulating material.

The face plate 10 supports a rotatable ratchet wheel 17 having ratchet teeth 18. Between the face plate and the back of tne ratchet wheel there is connected a spiral spring 19.y (sce Fig. 5), one end of the spring being attached to the face platevlO and the other end being attached to the ratchet wheel 17 for normally biasing the latter to its Zero or normal position. A stop, comprising abutments 2O and 21, carried preferably by the wheel and face plate, determine the normal or zero position, the spring being under p tension at such position. The front face of party answers, the relay 2 is energized due to the passage of current through the lines 62, 63, 64:, the contact 65, the line 66, `the winding of the relay 2 to the ground. Energization of the relay 2 results in the closure of a circuit for the relay 7, the current passing from the battery 69, through the contacts 68 and 67 the line 70, and the winding of the relay 7 to the ground. Energization ot the relay 7 results in movement of the contacts 71 and 72 into contact with the lines 73 and 7 t, respectively, to complete a circuit from the battery 85 for the motor magnet 25 in the manner more particularly hereinafter pointed out.

"W ith theA energization of the relay magnet 3 ot the supervisory lamp system, the contact 75 is drawn into contact with the line 74E, thereby closing the circuit, including the battery 80, for the energization of the relay 5, current passing from the battery 80, through the winding ot the relay', the line 77, the contact 78, the line 76, the contact 75, the line 74, the contact 72, which is closed by said relay 7, the lines 88 and 84, and the contact 8d to the ground, the latter contact being closed due to energization of the relay 1, already referred to.

Energization of the relay results in the closure ot a kcircuit for the relay 6 by drawing the contact 81 into Contact with the wire 82, said circuit including the battery 85, the line 86, the Winding of the rclay 6the line 82 andthe contact 8l to the ground.

Energization of the relay 6 results in closure of the contact 87 with the line 89 so that current may pass from the battery 85, through the lines 88 and 89 and through the contact 71, which has been moved into contact with the line 73 due to the energization of the relay 7, the line 73, the winding of the actuating or motor magnet 25, the line 90, and the clock 91 to the ground at 61. The clock 91 is arranged in the central office and may be of any well known type designed to `provide impulses of a fair degree of frequency. The clock is provided with a make-and-break contact device whereby the winding of the motor magnet 25 is subjected to intermittent actuating impulses responsive to the making and break-- ing of the contact by the clock. This causes the actuating pawl to be moved in a stepby-step manner and in synchronism with the oloclr.l

From the structure above set forth it will be seen that the ratchet wheel 17 is held 'from retrograde movement as soon as the plug is inserted in the called subscribers jack by means of the holding pawl et() which is maintained in engagement therewith by the holding magnet 26. Current from the battery passes through the winding of the motor magnet 2 5 and the connection there-` from to the ground is made and broken by the clock mechanism 91 therebyv energizing the motor magnet with a predeterniined timed frequency, whereby the pawl associ-A ated therewith imparts to the ratchet wheel a step-by-step movement in syn chronism with the clock. lt will be obvious that the ratchet wheel may be caused to operate through any desired arc within ,c

limits before means are actuated to signal the operator or interrupt the talking circuit. ln the particular system herein shown, the ratchet wheel is provided with a suiicient it is actuated for a distance ot' nearly 3600, a period of live minutes will have elapsed: however, it is obvious that the duration oin operation is determined by the time ot a standard call.

The face ot the ratchet wheel is `provided with a cam element 22 which is arn ranged to cooperate with the contact-'11, to engage the contact elements 15 and lll near the end of the period of movement of the ratchet wheel 1 7` or near the end ot the determined period oit the conrersation. lipon closure ot the contact-s 18 and la current flows `from the battery through the lanur 96, wire 97, contacts 13 and 1li, tothe ground' at 61, thereby notifying the erel'iange operator that the conversation period is about to expire. The operator thereupon notities the calling subscriber' that the period is number ot teeth so that when g;

about to expire and that if it is desired to continue the conirersation,r the subscriber should deposit more toll or i ter another call. It it is desired to contin e the couversation through a further period, the oper tor presses the key 58 which brei-.lts Contact at 59, thereby breaking the circuit for the holding magnet 36. whereupon the spring 40 for the holding` lf wl 'forces the latter out of er gement with the ratchet wheel 17 and t spring 19 connectedl between the face plate 1.0 and the ratchet wheel 17 acts on the latter and causes it to more back to Zero or starting position` and as soon as the operator allows the key 58 to go bach into engagement wth the.; Contact 59, the circuit through the hold .in ffnet is again completed and the holding pawl is brought back into eng ment with the ratchet wheel, the motor magnet 25 operat ing all the while, and as soon the holding pawl is reeengaged with the ratciet wheel` the latter is caused to move tor fard in :i step-by-step manner by means ot the pawl actuated by the motor magnet tor a furt1 period.

Should the operator tail to note the nal that the period of conversation is about to expire, or should the subscriber fail to pay anYT heed to a warning to that eFect. the other cam on` the ratchet wheel .17 operatively engages an insulated interrupti the e Fig'. 6.

finished, the operator removes the caliing; plug trom the jack, whereupon the relay l lis cle-energized and the contact 5st. is broken, thereby stop ping the 'flow of current trom the batteriY i J the holding paWl i0 to be mov disengaged position under tb spring 410. its 'soon as the is disengaged trom the ratchet spring,` associated With the latter back to its initial or zero position.

Briefly, apparatus in accordance With mv invention operates follows' subscriberreinoves his receiver whereupon vthe line lamp in the central station is illumine'd Vin the usual v ,thereup thc operator inserts an anentering` plug and iis-- certains from the subscriber the number sired. As soon 'as the sucrinp; plug is inserted, the relay 3 is Lcd, the om erator then inserts the. calling; plu;` ot the connecting` ccrd into the jack ci i subscriber, whereupon circa"y ately established for tbe holdin iii-eu the intermittently actuated motor for rupting the talkingcircuit. [is soon as t 1e called subscriber removes his recei hook switch is closed and a circuit is tablished for the Winding' ot the motor in: net 25, Which circuit is interrupted by mea" ot the central cloch as hereinbeitore referred to. The ratchet Wheel cic the motor device operates :tor a predetermined period Whereupon the cani Q2 closes the contacts 13 and 14: of the lamp 96, thereby completing a. circuit for the latter and permitting it bccome illumined. Shortly after the lamp cir cuit ismade, the other cam 23 on the 'tace the ratchet Wheel comes into enea -f With an insulated interrupt-er el f which serves to disengaeje the contacts and 16, thereby interriugtingr the tall-x gr circuit. As hereinbetore set iforth. the oper'ator may inform the subscriber that his conversation period is about to efzpf Vmay disengage the iololingn paul by.' mov- "inguthe hey 58 out ot ecea'frement with the iter `-contact 59, thereby brealri f, circuit the holding magnet 26, whereupon the bc ing paWl is moved out of engagement the ratchet Wheel and the sirnins` ben the latter immediately pulls it baci: t or initial position. therelr` ruption of the talkin@- circr-.it an.. ting conversation for urther period.

"While I have shown my invention in but .one form, it AWill be obvious to those skilled in the art that'it is not so limited, but is susceptible to various other chauffes and modiiications, Without departing ix im tbc spirit thereot, and l desire, therefore, that only such limitations shall be placed. theren upon as are imposed by the prior art or as are speciiically set [forth in tbe appended claims.

lihat I claim is l. ln a telephone ei-.ichange system. the combi .ation ot a calling suhscribeus line. a called subscribers liuc. comiectimr means for estal lishing,- commuuication between the lines, an interruptingij device s tbe eounectingmeans, and timing me us cooperating with the interrupting (larice and reudered opera-tive by the culled :mbscriber to secure interruption oi: communication a'ltcr the lapse of e predetermined interval.

In a telephone exchange system. the combination of a calling; sul icribers line. a called subscriherh line, connecting means for establishing); communication between the lines, an interrupting; device for the connecting means, timing; means ttor operating said device after a predetermined period, and means to initiate movement ot said timing neans upon the hook switch oil tbe called subscriber beine; closed.

ln a telephone exchange system. acounectine unit ior establishing commimicatiou between calling and called subscribers. comprisingi; connected lines, au interrupting dcvice in one of the lines, a means creating periodic electric impulses, means operable by said periodic impulses tor operating); said interrupting device, a circuit between the impulse creating device and the means operated thereby, and means operated by the closure ot the called subscribers bool switch for closing` said last named ciwuit.

ll. In a telephone exchange system, the combination of callingund called stations. a connecting cord including: talking' circuit elements, an iuteirupter tor one ot the said elements. actuating means to operate the interrupter after a predetermined period ol operation, and means to el'liect movement ot the actuating means rendered operative from the called station.

5. In a telephone system, the combination of a connecting cord including` talking circuit elements, an interruptm device for one of the said elements includ.. j contacts. step by-step mechanism, cam means carried by the step-by-step mechanism and adapted after a predetrmiued period of operation oi the latter to cooperate with the contacts to effect disengagement oit the latter. elcctromagnetic means cooperating with the stepby-step mechanism, and a switch which is opened and closed by a called subscriber for controlling the circuit ot said electro-magrnetic means.

6. In a telephone exchange system. the combination of a connecting cord including talking circuit elements, an interrupter in one of the said elements, a ratchet wheel, actuating and holding pawls for the ratchet wheel, electro-magnetic means 4for causing the holding pawl to engage the ratchet wheel responsive to the initial connection of the cord with a called subscribers line, electro-magnetic means for operating the actuating pawl including a timed make-andbreak means and responsive for its operation upon the establishment Vof communication.` with the called subscriber, a signal device including a circuit, contacts therefor, normally closed contacts for one of the talking circuit elements, cams carried by the ratchet wheel, one cooperating with the signal contacts to render the signal operative after a predetermined period of operation of the ratchet wheel and the other cooperating with the contacts of the talking circuit element to break the circuit therethrough shortly after the establishment of the signal circuit connection.

7. ln combination with a telephone eX- change system including calling and called siiibscribers .lines and a connecting means for the latter having talking circuit elements, an interrupting device for one of the talking circuitelements of the connecting means including normally closed contacts, means for disengaging the contacts after a predetermined interval, and means for rendering the disengaging means operative dependent upon closure of the called subscribers hook switch.

8. ln combination with a telephone eX- change system including calling and called subscribers7 lines and connecting means therefor having talking circuit elements, an interrupting device for one of the elements, a motor-device depending for its operation upon the closure of the called subscribers hook switch, and means carried by the motor-device for disengaging the contacts after a predetermined period of operation of the motor-device.

9. ln combination with a telephone exchange system including calling and called subscribers lines and connecting` means for the latter having talking circuit elements, an interrupting device for one of the said elements including normally closed contacts, a motor-device for opening the cont-acts after a predetermined period of operation, means to actuate the motor-device in response to closure of the called subscribers hook switch, a signal circuit, and means carried by the motor-device to effect closure of the signal circuit before interruption of the 'talking element contacts.

l0. In combination with a telephone eX- change system including calling and called subscribers lines and connecting means for the latter having talking circuit elements, an interrupting device for one of the said elements including normally closed contacts, a signal devi-1e including a circuit having normally open contacts, a cam wheel vhaving cam portions, one portion arranged to cooperate with the contacts to close the signal contacts before the talking circuit contacts are opened, and the other cam portion arranged to thereafter open the closed contacts,lratchet teeth on the cam wheel, a holding pawl cooperating with the ratchet teeth and normally 'disengaged therefrom, electromagnetic means for bringing the holding pawl into engagenfient with the ratchet teeth responsive to initial engagement of the connecting means with the called subscribers means for holding the element in position which is dependent upon closure of the called subscriberls hook swith for energization, and manual means for interrupting the circuit of the holding means whereby the element may be allowed to return to initial position.

l2. ln combination with a. telephone eX- change system including calling and called subscribers lines and connecting means therefor having talking circuit elements, normally closed contacts for one of said elements, a signal device, moveable means cooperating with the signal device and contacts to render the signal operative after movement of the moveable means from its initial position for a predetermined period and to open the 4contacts an interval after the signal is rendered operative, means for causing movement of the moveable means, means opposing movement of the moveable means and tending to return. it to initial position, and means under control of the operator for rendering the movement causing means ineffective.

13. ln combination with a telephone eX- change system including calling and called subscribers lines and connecting means therefor having talking circuit elements, normally closed contacts for one of the elements, a signal device, a circuit therefor including normally open contacts, a ratchet wheel having 'cam portions effective in sequence to close the open contacts and open4 the closed contacts, means to bias the ratchet wheel into a zero or initial position, a holdi'n'g' pawl', means for biasing the holding pawl out of engagement with the ratchet wheel, electro-magnetic means opposing the biasing means and adapted to maintain the holding pawl' in engagement with the ratchet wheel, an actuatingpawl, means. Ytor biasing the actuating pawl out of engagement with` the ratchet Wheel, electro-magnetic means for causing the actuating pawl to operatively engage the ratchet wheel, cloclr mechanism for making and breaking the circuit of the second electro-magnetic means whereby the latter is intermittently energizyed'` and `the actuating pawl is given an intermittent and .reciprocatory movement to intermittently move the ratchet wheel, and means under the control of the operator for breaking the circuit of the first electro-inagne-tic means whereby the ratchet wheel may bereturned to zero or initial position before the closedcontacts are opened.

14. ln combination with a telephone er;- change system including calling and called subscribers lines and connecting means therefor having talking circuit elements, normally closed contacts for one oithe eleirireiit'sgl a ratchet wheel having a cam porti'onto open the closed contacts after movement o't the wheel a predetermined degrc, tromits ini-tial or Zero position, means to biaslthe ratchet wheel into a Zero or initial 1 osition,` a holding pawl, means for biasing the-holding pawl out oi engagement withv the ratchet wheel, electro-magnetic means opposingY the biasing means and adapted to maintainthe holding pawl in engagement with' the ratchet wheel, an actuating. pawl, means for biasing the actuating pawl out oil engagement with the ratchet wheel, el .Y magnetic means for causing the actuating pawl to operatively engage the ratchet Wheel, and clock mechanism for making and breaking the circuit of the second electrorfragnetifc means whereby the latter is inter-- mittently energizedl and the actuating pawl is given an intermittent and reciprocatory movement to intermittently move the ratchet wheel.

15'. In a telephone system, the combination oi a signal circuit including a signal and contacts, a talking circuit including contacts, a called subscribers hoolr switch, mechanism ior closing the first contacts and opening the second contacts sequentially, and means rendered eli'ective by closure of said heel; switch to secure operation of said mechanism. y

16. ln a telephone system, the combination oi calling, called, and central stations, circuits tor connecting the stations, a circuit interruptor at the central station, means under the control of the called station for operating the interruptor. and a signal at the central station which is operated by said means before the interruptor is operated.

17. ln a telephone s vstei'n, the combination ot a talking circuit including contacts, a cam 'for disengaging the contacts, tiineecontrolled nwclianisni For operating the cam, and means 'tor resetting the cam body to its starting position without interrupting of thc talking circuit.

1S. In a telephone system, the combination oiI a talking circuit including` contacts, a signal circuit including a signal and contarts, a cam body hr a cam portion for closing the latter contacts and u cam portion :tor opening the first c: tirets in sequence, and time-controlled mechanism .for actuating the cam.

19. ln telephone syst-cin, thc combination of a talling circuit including contacts, a signal circuit including contacts, a cam body having a cam portion for opening the first contacts `and a cam portion tor closing the. second contacts before the lirst contacts are opt-ne l, time-controlled mechanism 'ior moving the. body from a starting position, and means for resetting the cum body to its starting position without interruption of the talking circuit.

In testimony whereof I have hereunto sub scribed my name this 16 day oft September, 1920.

ARTHUR M. CRICHTON. 

